The “Printing Working Group” (PWG) is a consortium of printing and network vendors formally allied with the IEEE Industry Standards and Technology Organization (IEEE-ISTO) and responsible for the IPP specifications. PWG is in the process of defining an “IPP System Service” for general management and control purposes. DCPI complements and augments the “IPP System Service” and can be designed for vendor and device specific control purposes.
As per the Internet Engineering Task Force (IETF) IPP specifications—RFCs 2910 and 2911 (updated by RFCs 3380, 3381, 3382, 3510, 3995, 3996 and 7472), the IPP request/response header includes the following:
FieldLength (in bytes)Notesversion-number21.0-1.1 and 2.0-2.2operation-id (request)2Example operation -orPrint-Job.status-code (responseExample status -OK or bad-requestrequest-id4Used to mapresponses torequestsattribute-group(s)n-bytesOperation/Jobattributes like coloror copiesend-of-attributes1End markerdataq-bytesOptional